Question

A food scientist hypothesized that the processing used to concentrate juice destroys some of the vitamin C in orange juice. He measured vitamin C in fresh juice and juices made from liquid and frozen concentrate.

How does the process of concentration affect the vitamin C content of orange juice?

Graph

Answer 1

Short answer
- Concentration (evaporative heating, exposure to oxygen/light, and storage) tends to reduce vitamin C. Juices made from concentrate usually have lower vitamin C than freshly squeezed juice.

If you want a graph
I can plot your data if you send it. Below is an example (hypothetical) bar chart and the code to produce it. The example assumes vitamin C measured as mg per 100 mL for three groups: Fresh, Frozen-concentrate (reconstituted), Liquid-concentrate (reconstituted). Example means: Fresh = 50 mg/100 mL, Frozen = 40 mg/100 mL, Liquid = 35 mg/100 mL.

Python (matplotlib) example
- Copy/paste and run in a Python environment.

import matplotlib.pyplot as plt
import numpy as np

groups = ['Fresh', 'Frozen concentrate', 'Liquid concentrate']
means = [50, 40, 35] # example mg vitamin C per 100 mL
std_devs = [3, 4, 4.5] # example SDs for error bars
x = np.arange(len(groups))

fig, ax = plt.subplots(figsize=(6,4))
bars = ax.bar(x, means, yerr=std_devs, capsize=6, color=['#4CAF50','#2196F3','#FFC107'])
ax.set_xticks(x)
ax.set_xticklabels(groups)
ax.set_ylabel('Vitamin C (mg per 100 mL)')
ax.set_title('Effect of concentration on vitamin C (example data)')
ax.set_ylim(0, max(means)+max(std_devs)+10)
for i,m in enumerate(means):
ax.text(i, m+std_devs[i]+1, f'{m} mg', ha='center')
plt.tight_layout()
plt.show()

R (ggplot2) example
- Copy/paste and run in R.

library(ggplot2)
groups <- c('Fresh','Frozen concentrate','Liquid concentrate')
means <- c(50,40,35)
sd <- c(3,4,4.5)
df <- data.frame(group=factor(groups, levels=groups), mean=means, sd=sd)
ggplot(df, aes(x=group, y=mean, fill=group)) +
geom_bar(stat='identity', width=0.6) +
geom_errorbar(aes(ymin=mean-sd, ymax=mean+sd), width=0.2) +
ylab('Vitamin C (mg per 100 mL)') +
ggtitle('Effect of concentration on vitamin C (example data)') +
theme_minimal() + theme(legend.position='none')

Interpreting results and analysis
- If you have measurements from multiple samples per group, use one-way ANOVA to test for overall differences across the three groups; follow with Tukey post-hoc comparisons. If assumptions are violated, use Kruskal–Wallis and pairwise Wilcoxon tests with p-value correction.
- Control for reconstitution (concentrates should be reconstituted to the same soluble solids/volume as fresh juice).
- Report means ± SD and sample sizes.

Why vitamin C is lost during concentration
- Heat: ascorbic acid is heat-sensitive and degrades during evaporation/concentration.
- Oxidation: exposure to oxygen and light during processing accelerates loss.
- Storage: concentrate storage time/conditions (temperature, oxygen) further reduce vitamin C.

If you want
- I can plot your real data (CSV or numbers).
- I can run the appropriate statistical test and report p-values and confidence intervals if you provide the raw measurements.